Continuous carbon dioxide (CO2) emission from anthropogenic sources causes severe environmental issues such as global warming. The largest CO2-emitting industrial sources are coal-fired power plants, in which post-combustion capture is often utilized to remove CO2 from exhaust gas generated from combustion of fossil fuels. Flue gas from power plants is composed of carbon dioxide (˜15-16%), water vapor (˜5-7%) and nitrogen (˜70-75%) at ˜1 bar.
In order to separate and capture CO2 from flue gas emissions at a power plant, monoethanol amine (MEA)-based aqueous solution is conventionally employed.
However, this wet-process requires a high-energy cost to regenerate absorbents because of not only an inherent high heat capacity of water in MEA solution but also chemisorption of CO2 on MEA. Approximately 30% of energy produced from the power plants is usually wasted to regenerate the aqueous MEA